public class User implements Serializable{
public String name;
public String surname;
public List<Picked> pickedBooks = new ArrayList<>();
// Code omitted.
}
然后选择类:
public class Picked {
public Book book;
public int period;
public int cost;
// Code omitted.
}
和类书:
public class Book {
public String name;
public String bookTitle;
public int howMany;
// Code omitted.
}
所以主要是我创建了新用户并将其序列化:
User user = new User();
user.setName("John");
user.setSurname("James");
String fileName = "data.bin";
try (ObjectOutputStream os = new ObjectOutputStream(new FileOutputStream(fileName))) {
os.writeObject(user);
} catch (IOException ex) {
Logger.getLogger(Library.class.getName()).log(Level.SEVERE, null, ex);
}
一切正常,但如果我这样做:
Book book = new Book("Dan Brown", "Angels and Demons", 1);
Picked pck = new Picked(book, 20, 2);
user.add(pck);
然后我想序列化对象用户,程序崩溃了。 我得到的输出是:
java.io.NotSerializableException: at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1183) at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:347) at java.util.ArrayList.writeObject(ArrayList.java:742) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:606) at java.io.ObjectStreamClass.invokeWriteObject(ObjectStreamClass.java:988) at java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1495) at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1431) at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1177) at java.io.ObjectOutputStream.defaultWriteFields(ObjectOutputStream.java:1547) at java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1508) at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1431) at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1177) at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:347)
最佳答案
Picked
和Book
也需要实现Serializable
。
关于java - 序列化包含对象 ArrayList 的对象,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/23794576/